experiment: Factor out Ed25519 implementation into a single file.

* cipher/pkey-ed25519.c: New.

Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>

4 files changed, 283 insertions, 189 deletions

diff --git a/cipher/Makefile.am b/cipher/Makefile.am
index fb41d55d..b0f0f3fc 100644
--- a/cipher/Makefile.am
+++ b/cipher/Makefile.am
@@ -57,7 +57,7 @@ libcipher_la_SOURCES = \
 	cipher-gcm-siv.c \
 	cipher-selftest.c cipher-selftest.h \
 	pubkey.c pubkey-internal.h pubkey-util.c \
-	pkey.c \
+	pkey.c pkey-internal.h pkey-ed25519.c \
 	md.c \
 	mac.c mac-internal.h \
 	mac-hmac.c mac-cmac.c mac-gmac.c mac-poly1305.c \
diff --git a/cipher/pkey-ed25519.c b/cipher/pkey-ed25519.c
new file mode 100644
index 00000000..e0edbf6d
--- /dev/null
+++ b/cipher/pkey-ed25519.c
@@ -0,0 +1,224 @@
+/* pkey-ed25519.c  -	PKEY API implementation for Ed25519
+ * Copyright (C) 2021 g10 Code GmbH
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser general Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: LGPL-2.1+
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <errno.h>
+
+#include "g10lib.h"
+#include "gcrypt-int.h"
+#include "pkey-internal.h"
+
+gcry_error_t
+_gcry_pkey_ed25519_sign (gcry_pkey_hd_t h,
+                         int num_in, const unsigned char *const in[],
+                         const size_t in_len[],
+                         int num_out, unsigned char *out[], size_t out_len[])
+{
+  gcry_error_t err = 0;
+  gcry_sexp_t s_sk = NULL;
+  gcry_sexp_t s_msg= NULL;
+  gcry_sexp_t s_sig= NULL;
+
+  gcry_sexp_t s_tmp, s_tmp2;
+
+  if ((h->flags & GCRY_PKEY_FLAG_CONTEXT))
+    {
+      if (num_in != 2 || (h->flags & GCRY_PKEY_FLAG_PREHASH))
+        return gpg_error (GPG_ERR_INV_ARG);
+    }
+  else
+    {
+      if (num_in != 1)
+        return gpg_error (GPG_ERR_INV_ARG);
+    }
+
+  if (num_out != 2)
+    return gpg_error (GPG_ERR_INV_ARG);
+
+  if (h->pk)
+    err = sexp_build (&s_sk, NULL,
+                      "(private-key"
+                      " (ecc"
+                      "  (curve \"Ed25519\")"
+                      "  (flags eddsa)"
+                      "  (q %b)"
+                      "  (d %b)))",
+                      (int)h->pk_len, h->pk,
+                      (int)h->sk_len, h->sk);
+  else
+    err = sexp_build (&s_sk, NULL,
+                      "(private-key"
+                      " (ecc"
+                      "  (curve \"Ed25519\")"
+                      "  (flags eddsa)"
+                      "  (d %b)))",
+                      (int)h->sk_len, h->sk);
+  if (err)
+    return err;
+
+  if ((h->flags & GCRY_PKEY_FLAG_CONTEXT))
+    err = sexp_build (&s_msg, NULL,
+                      "(data"
+                      " (flags eddsa)"
+                      " (hash-algo sha512)"
+                      " (value %b)"
+                      " (label %b))",
+                      (int)in_len[0], in[0],
+                      (int)in_len[1], in[1]);
+  else if ((h->flags & GCRY_PKEY_FLAG_PREHASH))
+    err = sexp_build (&s_msg, NULL,
+                      "(data"
+                      " (flags eddsa prehash)"
+                      " (hash-algo sha512)"
+                      " (value %b))", (int)in_len[0], in[0]);
+  else
+    err = sexp_build (&s_msg, NULL,
+                      "(data"
+                      " (flags eddsa)"
+                      " (hash-algo sha512)"
+                      " (value %b))", (int)in_len[0], in[0]);
+  if (err)
+    {
+      sexp_release (s_sk);
+      return err;
+    }
+
+  err = _gcry_pk_sign (&s_sig, s_msg, s_sk);
+  sexp_release (s_sk);
+  sexp_release (s_msg);
+  if (err)
+    return err;
+
+  out[0] = out[1] = NULL;
+  s_tmp2 = NULL;
+  s_tmp = sexp_find_token (s_sig, "sig-val", 0);
+  if (s_tmp)
+    {
+      s_tmp2 = s_tmp;
+      s_tmp = sexp_find_token (s_tmp2, "eddsa", 0);
+      if (s_tmp)
+        {
+          sexp_release (s_tmp2);
+          s_tmp2 = s_tmp;
+          s_tmp = sexp_find_token (s_tmp2, "r", 0);
+          if (s_tmp)
+            {
+              out[0] = sexp_nth_buffer (s_tmp, 1, &out_len[0]);
+              sexp_release (s_tmp);
+            }
+          s_tmp = sexp_find_token (s_tmp2, "s", 0);
+          if (s_tmp)
+            {
+              out[1] = sexp_nth_buffer (s_tmp, 1, &out_len[1]);
+              sexp_release (s_tmp);
+            }
+        }
+    }
+  sexp_release (s_tmp2);
+
+  if (out[0] == NULL || out[1] == NULL)
+    err = gpg_error (GPG_ERR_BAD_SIGNATURE);
+
+  sexp_release (s_sig);
+
+  return err;
+}
+
+gcry_error_t
+_gcry_pkey_ed25519_verify (gcry_pkey_hd_t h,
+                           int num_in, const unsigned char *const in[],
+                           const size_t in_len[])
+{
+  gcry_error_t err = 0;
+  gcry_sexp_t s_pk = NULL;
+  gcry_sexp_t s_msg= NULL;
+  gcry_sexp_t s_sig= NULL;
+
+  if ((h->flags & GCRY_PKEY_FLAG_CONTEXT))
+    {
+      if (num_in != 4 || (h->flags & GCRY_PKEY_FLAG_PREHASH))
+        return gpg_error (GPG_ERR_INV_ARG);
+    }
+  else
+    {
+      if (num_in != 3)
+        return gpg_error (GPG_ERR_INV_ARG);
+    }
+
+  err = sexp_build (&s_pk, NULL,
+                    "(public-key"
+                    " (ecc"
+                    "  (curve \"Ed25519\")"
+                    "  (flags eddsa)"
+                    "  (q %b)))",
+                    (int)h->pk_len, h->pk);
+  if (err)
+    return err;
+
+  if (h->flags & GCRY_PKEY_FLAG_CONTEXT)
+    err = sexp_build (&s_msg, NULL,
+                      "(data"
+                      " (flags eddsa)"
+                      " (hash-algo sha512)"
+                      " (value %b)"
+                      " (label %b))",
+                      (int)in_len[0], in[0],
+                      (int)in_len[3], in[3]);
+  else if ((h->flags & GCRY_PKEY_FLAG_PREHASH))
+    err = sexp_build (&s_msg, NULL,
+                      "(data"
+                      " (flags eddsa prehash)"
+                      " (hash-algo sha512)"
+                      " (value %b))", (int)in_len[0], in[0]);
+  else
+    err = sexp_build (&s_msg, NULL,
+                      "(data"
+                      " (flags eddsa)"
+                      " (hash-algo sha512)"
+                      " (value %b))", (int)in_len[0], in[0]);
+  if (err)
+    {
+      sexp_release (s_pk);
+      return err;
+    }
+
+  err = sexp_build (&s_sig, NULL,
+                    "(sig-val(eddsa(r %b)(s %b)))",
+                    (int)in_len[1], in[1],
+                    (int)in_len[2], in[2]);
+  if (err)
+    {
+      sexp_release (s_msg);
+      sexp_release (s_pk);
+      return err;
+    }
+
+  err = _gcry_pk_verify (s_sig, s_msg, s_pk);
+
+  sexp_release (s_sig);
+  sexp_release (s_msg);
+  sexp_release (s_pk);
+
+  return err;
+}
diff --git a/cipher/pkey-internal.h b/cipher/pkey-internal.h
new file mode 100644
index 00000000..a63206ed
--- /dev/null
+++ b/cipher/pkey-internal.h
@@ -0,0 +1,55 @@
+/* pkey-internal.h  - Internal defs for pkey.c
+ * Copyright (C) 2021 g10 Code GmbH
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser general Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: LGPL-2.1+
+ */
+
+gcry_error_t _gcry_pkey_ed25519_sign (gcry_pkey_hd_t h,
+                                      int num_in, const unsigned char *const in[],
+                                      const size_t in_len[],
+                                      int num_out, unsigned char *out[],
+                                      size_t out_len[]);
+
+gcry_error_t _gcry_pkey_ed25519_verify (gcry_pkey_hd_t h,
+                                        int num_in, const unsigned char *const in[],
+                                        const size_t in_len[]);
+
+gcry_error_t _gcry_pkey_ed448_sign (gcry_pkey_hd_t h,
+                                    int num_in, const unsigned char *const in[],
+                                    const size_t in_len[],
+                                    int num_out, unsigned char *out[],
+                                    size_t out_len[]);
+
+gcry_error_t _gcry_pkey_ed448_verify (gcry_pkey_hd_t h,
+                                      int num_in, const unsigned char *const in[],
+                                      const size_t in_len[]);
+
+
+struct gcry_pkey_handle {
+  int algo;
+  unsigned int flags;
+
+  /* FIXME: Use of union would be better, here.  */
+
+  int curve;
+
+  unsigned char *pk;
+  size_t pk_len;
+
+  unsigned char *sk;
+  size_t sk_len;
+};
diff --git a/cipher/pkey.c b/cipher/pkey.c
index 207d60aa..a6ed67de 100644
--- a/cipher/pkey.c
+++ b/cipher/pkey.c
@@ -27,21 +27,7 @@
 
 #include "g10lib.h"
 #include "gcrypt-int.h"
-
-struct gcry_pkey_handle {
-  int algo;
-  unsigned int flags;
-
-  /* FIXME: Use of union would be better, here.  */
-
-  int curve;
-
-  unsigned char *pk;
-  size_t pk_len;
-
-  unsigned char *sk;
-  size_t sk_len;
-};
+#include "pkey-internal.h"
 
 gcry_error_t
 _gcry_pkey_vopen (gcry_pkey_hd_t *h_p, int algo, unsigned int flags,
@@ -176,183 +162,12 @@ _gcry_pkey_op (gcry_pkey_hd_t h, int cmd,
                int num_out, unsigned char *out[], size_t out_len[])
 {
   gcry_error_t err = 0;
-  gcry_sexp_t s_sk = NULL;
-  gcry_sexp_t s_pk = NULL;
-  gcry_sexp_t s_msg= NULL;
-  gcry_sexp_t s_sig= NULL;
 
   /* Just for Ed25519 for now.  Will support more...  */
   if (cmd == GCRY_PKEY_OP_SIGN)
-    {
-      gcry_sexp_t s_tmp, s_tmp2;
-
-      if ((h->flags & GCRY_PKEY_FLAG_CONTEXT))
-        {
-          if (num_in != 2 || (h->flags & GCRY_PKEY_FLAG_PREHASH))
-            return gpg_error (GPG_ERR_INV_ARG);
-        }
-      else
-        {
-          if (num_in != 1)
-            return gpg_error (GPG_ERR_INV_ARG);
-        }
-
-      if (num_out != 2)
-        return gpg_error (GPG_ERR_INV_ARG);
-
-      if (h->pk)
-        err = sexp_build (&s_sk, NULL,
-                          "(private-key"
-                          " (ecc"
-                          "  (curve \"Ed25519\")"
-                          "  (flags eddsa)"
-                          "  (q %b)"
-                          "  (d %b)))",
-                          (int)h->pk_len, h->pk,
-                          (int)h->sk_len, h->sk);
-      else
-        err = sexp_build (&s_sk, NULL,
-                          "(private-key"
-                          " (ecc"
-                          "  (curve \"Ed25519\")"
-                          "  (flags eddsa)"
-                          "  (d %b)))",
-                          (int)h->sk_len, h->sk);
-      if (err)
-        return err;
-
-      if ((h->flags & GCRY_PKEY_FLAG_CONTEXT))
-        err = sexp_build (&s_msg, NULL,
-                          "(data"
-                          " (flags eddsa)"
-                          " (hash-algo sha512)"
-                          " (value %b)"
-                          " (label %b))",
-                          (int)in_len[0], in[0],
-                          (int)in_len[1], in[1]);
-      else if ((h->flags & GCRY_PKEY_FLAG_PREHASH))
-        err = sexp_build (&s_msg, NULL,
-                          "(data"
-                          " (flags eddsa prehash)"
-                          " (hash-algo sha512)"
-                          " (value %b))", (int)in_len[0], in[0]);
-      else
-        err = sexp_build (&s_msg, NULL,
-                          "(data"
-                          " (flags eddsa)"
-                          " (hash-algo sha512)"
-                          " (value %b))", (int)in_len[0], in[0]);
-      if (err)
-        {
-          sexp_release (s_sk);
-          return err;
-        }
-
-      err = _gcry_pk_sign (&s_sig, s_msg, s_sk);
-      sexp_release (s_sk);
-      sexp_release (s_msg);
-      if (err)
-        return err;
-
-      out[0] = out[1] = NULL;
-      s_tmp2 = NULL;
-      s_tmp = sexp_find_token (s_sig, "sig-val", 0);
-      if (s_tmp)
-        {
-          s_tmp2 = s_tmp;
-          s_tmp = sexp_find_token (s_tmp2, "eddsa", 0);
-          if (s_tmp)
-            {
-              sexp_release (s_tmp2);
-              s_tmp2 = s_tmp;
-              s_tmp = sexp_find_token (s_tmp2, "r", 0);
-              if (s_tmp)
-                {
-                  out[0] = sexp_nth_buffer (s_tmp, 1, &out_len[0]);
-                  sexp_release (s_tmp);
-                }
-              s_tmp = sexp_find_token (s_tmp2, "s", 0);
-              if (s_tmp)
-                {
-                  out[1] = sexp_nth_buffer (s_tmp, 1, &out_len[1]);
-                  sexp_release (s_tmp);
-                }
-            }
-        }
-      sexp_release (s_tmp2);
-
-      if (out[0] == NULL || out[1] == NULL)
-        err = gpg_error (GPG_ERR_BAD_SIGNATURE);
-
-      sexp_release (s_sig);
-    }
+    err = _gcry_pkey_ed25519_sign (h, num_in, in, in_len, num_out, out, out_len);
   else if (cmd == GCRY_PKEY_OP_VERIFY)
-    {
-      if ((h->flags & GCRY_PKEY_FLAG_CONTEXT))
-        {
-          if (num_in != 4 || (h->flags & GCRY_PKEY_FLAG_PREHASH))
-            return gpg_error (GPG_ERR_INV_ARG);
-        }
-      else
-        {
-          if (num_in != 3)
-            return gpg_error (GPG_ERR_INV_ARG);
-        }
-
-      err = sexp_build (&s_pk, NULL,
-                        "(public-key"
-                        " (ecc"
-                        "  (curve \"Ed25519\")"
-                        "  (flags eddsa)"
-                        "  (q %b)))",
-                        (int)h->pk_len, h->pk);
-      if (err)
-        return err;
-
-      if (h->flags & GCRY_PKEY_FLAG_CONTEXT)
-        err = sexp_build (&s_msg, NULL,
-                          "(data"
-                          " (flags eddsa)"
-                          " (hash-algo sha512)"
-                          " (value %b)"
-                          " (label %b))",
-                          (int)in_len[0], in[0],
-                          (int)in_len[3], in[3]);
-      else if ((h->flags & GCRY_PKEY_FLAG_PREHASH))
-        err = sexp_build (&s_msg, NULL,
-                          "(data"
-                          " (flags eddsa prehash)"
-                          " (hash-algo sha512)"
-                          " (value %b))", (int)in_len[0], in[0]);
-      else
-        err = sexp_build (&s_msg, NULL,
-                          "(data"
-                          " (flags eddsa)"
-                          " (hash-algo sha512)"
-                          " (value %b))", (int)in_len[0], in[0]);
-      if (err)
-        {
-          sexp_release (s_pk);
-          return err;
-        }
-
-      err = sexp_build (&s_sig, NULL,
-                        "(sig-val(eddsa(r %b)(s %b)))",
-                        (int)in_len[1], in[1],
-                        (int)in_len[2], in[2]);
-      if (err)
-        {
-          sexp_release (s_msg);
-          sexp_release (s_pk);
-          return err;
-        }
-
-      err = _gcry_pk_verify (s_sig, s_msg, s_pk);
-
-      sexp_release (s_sig);
-      sexp_release (s_msg);
-      sexp_release (s_pk);
-    }
+    err = _gcry_pkey_ed25519_verify (h, num_in, in, in_len);
   else
     err = gpg_error (GPG_ERR_INV_OP);